Cutter



Nov. 18, 1947.

E, R. MILLER CUTTER Filed Nov. 14," 1945 8 am 5 ow Tw E INVENTOR EMIL EnMIL LEI-2' 'ATTORNEY Patented Nov. 18, 1947 CUTTER Emil R. Miller,United States Navy, Bremerton, Wash.

Application November 14, 1945, Serial No. 628,628

3 Claims.

(Granted under the act of March amended April 30, 1928; 370 O.

This invention relates to cutters and more particularly to cutters forth corroded edges of handhole openings in boiler headers containingsuper-heater tubes.

Such headers generally consist of a chamber having a wall provided withcircular openings through which the super-heater tubes may be observedand, in addition, elliptical or oval openings having closure platessecured in a suitable manner, as by dogs, against the edges of theelliptical openings interiorly of the chamber. While a gasket is usuallyinterposed between the closure plates and edges of the openings actionof the steam in the header causes corrosion of the plate seats whichresults in leakage from the header. The plate seats at the ellipticalopening edge thus must be periodically ground or refaced.

Because of the shape of the elliptical openings the refacing operationis made difficult, it being tedious and inefficient to normally hold acutter against the irregularly shaped edges to be cut in the refacingoperations.

Objects of the present invention, are, therefore, to provide forfacilely, economically and efiiciently refacing hand-hole plate seats ofirregular shape in the interior of boiler headers; and to provideimproved elements and arrangements thereof in a cutter and mountingtherefor.

In accomplishing these and other objects of the present invention, Ihave provided improved details of structure the preferred form of whichis illustrated in the accompanying drawing wherein:

Fig. 1 is a vertical cross-sectional view through a cutter embodyingthis invention showing its relation to a header and handhole thereinedges of which are to be refaced.

Referring more in detail to the drawing:

l designates the top wall of a boiler header comprising a chamber thatcontains superheater tubes. Headers of this character are normallyprovided with circular observation holes 2 and 3 and, in addition,elliptical, oval or other irregularly shaped openings 4 are provided inthe header wall I. The openings 4 constitute handholes by which accessmay be had to the tubes in the header for desired work on the tubes. Thehandholes 4 are normally provided with closures which constitute plates,the upper edges of which are arranged in seats 5 in the outer lowerperiphery of the header wall portions that bound the handholes.

Even though gaskets are normally inserted between the handhole closuresand seats therefor,

3, 1883, as G. 757) the seats corrode, as indicated at 6, the result ofwhich is a leakage out of the handholes. The corroded portions of thehandhole closure seats are difiicult to treat because of their positionand irregular shape, and, as indicated above, it is the purpose of thisinvention to overcome that difficulty.

1 designates a base member which may be of any suitable rigid materialand is of preferably rectangular shape. The base member 1 is providedwith stud bolts 8 and 9 at its ends extending upwardly through thecircular openings 2 and 3 adjacent the elliptical handhole 4 the shanksof which bolts are secured, as by nuts [0 and II, to the supportingblocks l2 and I3 that bridge the openings 2 and 3.

Mounted on the base member 1 is an accurately machined plate l4 that issecured to the base by counter-sunk screws l5 and Hi, the inner ends ofwhich engage and secure to the plate Hi the spacing blocks I! and I8.The machined plate M generally conforms to the shape of the base member1 and is of a length sufficient to bridge the handhol 4 in such a mannerthat the spacing blocks [1 and I8 may engage the inner surface of theheader wall I at opposite ends of the handhole 4.

A cam base I9 is fixedly mounted on the machine plate l4, as by thescrews and 2|, the heads of which are counter-sunk in the upper surfaceof a cam 22 superimposed upon the cam base l9.

The cam 22 is of a shape conforming to the periphery of the handhole 4but of less surface area than the area of the handhole to provide apassageway 23 between the cam face 24 andthe inner face 25 of the wallportion defining the handhole 4. The lower face of the cam may beprovided with an offset 26, if desired, for a purpose later described.The cam base l9 and cam 22 are fixedly mounted, as by a pin 21, on theenlarged end 28 of a spindle 29. A washer 30 is sleeved on the spindle29 and rests on the upper surface of the cam 22.

3| designates a cross-head of suitable shape and size to bridge thehandhole 4 provided witha central aperture 32 of greater diameter thanthe spindle 29 to allow play of the cross-head on the spindle. A washer33 in cooperation with lock nuts 34 retains the cross-head 3| on thespindle. The spindle is adjusted relative to the header wall I by theadjusting screw 35.

The cross-head 3| is provided at .one end with a handle 36 formanipulating the same and an aperture 31 at its other end for receivingth shank 38 of a cutter assembly 39, the assembly being positioned inthe aperture 31 by washers 40 and 4| that are suitably secured to theshank on opposite faces of the cross-head. The shank is adjustablevertically relative to the crosshead by turning the same and tighteningthe lock nuts 42 down on the washer 40.

The washers 40 and 4| on the cutter assembly shank are so arrangedrelative to the cross-head that a portion 43 of the shank is availableto serve as a cam follower loosely and slidably engageable with theperiphery of the cam 24 in relatively closely spaced relation to thebound edges of the handhole 4.

The cutter 44 proper is mounted on the lower end of the cutter shank andis preferably provided with teeth on its side and upper surface of sucha character as to act on the corroded portion 6 of the handhole edges.The cutter does not act on the cam because it may follow in the ofiset.26 providedin the lower surface of the cam.

Ihe upper end of the cutter assembly shank is ,provided with a fitting45 of a character suitable :for receiving a conventional drivingmechanism of any desired t p Operation The operation of an apparatusconstructed as described is as follows:

The cutter shank .is adjusted vertically in the cross-head 3'! toposition the teeth on the upper face of the cutter proper in engagementwith the corroded portion v6 of the handhole edges. A power driveis thenapplied to the cutter shank fitting-45 to actuate the cutter and reface,grind or otherwise work upon the corroded handhole plate seat 5. Thehandle 36 is then manipulated to rotate the cross-head 3l in such amanner that the shank portion 43 of the cutter assembly, follows theface 24 of the cam around the peripheryof the cam, Because the cam is ofthe same shape as the handhole 4, mere rotation of the cross-head 31effects refacing of the handhole plate seat.

'Itwill be recognized that since the handhole 4 and cam 22 are, in thisinstance elliptical or oval in shape, they each have opposed axes ofdifferent lengths and the cutter must move from left to right, .as shownin the drawing, to accurately follow the cam and seat during travel ofthe cutter around'the cam. The size of the aperture 32 in the cross-headprovides for such movement to allow retraction of the cutter when thecutter approaches the shorter axis or diameter of the'handhole as wellas protraction .of the cutter adjacent the edges of the handhole plateseat adjacent its longer axis.

After the cutter has refaced the handhole plate seat '5, the dogs orblocks I2 and I3 supporting the base-member I may beremoved and thecutter assembly, including the mounting therefor, may be removed fromthe handhole 4 and reapplied to the header wall Iin position to refaceanother handhol plate seat.

While I have shown but one embodiment of my invention, it is apparentthat the device is susceptible to modification Without departing fromthe spirit of the invention. I do not wish, therefore, to be limited bythe disclosures set forth, but only by the scope of the appended claims.

The invention described herein may be manufactured and used by or forthe Government of 0 Number the United States of America for governmentalpurposes without the payment of an royalties thereon or therefor,

I claim:

1. In a device of the character described, a base member engageable witha wall of a chamber having an opening edges of which are to be workedupon, a plate mounted on the base member and adjustably engageable withsaid wall to align said plate in relation to said wall, a cam mounted onsaid plate having a face corresponding to the shape of said opening andof less surface area to provide a passage between the cam and the edgesof the opening, a spindle on the cam, means on the spindle for adjustingthe cam relative to said opening, a cross-head having an opening ofgreater diameter than the spindle for rotatably mounting the cross-headon the spindle and allow play thereof on the spindle, said crossheadhaving a handle portion for rotating the same, a cutter rotatablymounted on the crosshead having cutting portions engageable with edgesof said opening, a cam follower on thecutter to guide the cutter aroundthe cam in engagement with said opening edges, and means for actuatingsaid cutter.

2. In a device of the character described, a base member engageable witha wall of a chamber having an opening edges of which are to be workedupon, a plate mounted'on the base member and adjustably engageable withsaid wall to align said plate in relation to said wall, a cam mounted onsaid plate having a face corresponding to the shape of said openingandof less surface area to provide a passage between the cam and theedges of the opening, a spindle on the cam, a cross-head having anopening of greater diameter than the spindle for rotatably mounting thecross-head on the spindle and provide play therefor on the spindle, acutter rotatably mounted on the cross-head having cutting portionsengageable with edges of said opening, a cam follower on the cutter toguide the cutter around the cam in engagement with said opening edges,and means for actuating said cutter.

3. In a device of the character described, a base member engageable witha wall of a chamber having an opening edges of which are to be workedupon, a cam mounted on said base member, having a face corresponding tothe shape of said opening and of less surface area to provide a passagebetween the cam and the edges of the opening, a spindle on the cam, across-head having an opening of greater diameter than the spindle forrotatably mounting the cross-head on thespindle and provide playtherefor on the spindle, a cutter rotatably mounted on the cross headhaving cutting portions engageable with edges of said opening, a camfollower on the cutter to guide the cutter around the cam in engagementwith said opening edges, and means for actuating said cutter.

EMIL R. MILLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Name Date Kelley Dec. 3, 19.12 Wiglenda Aug. -6,1929

